Closure assemblies for use with collapsible tube dispensers are known to the art, and which serve to control the discharge of liquids and soft solids from the collapsible tube, the closures being intended to close automatically and cut off the flow of the substance when the squeezing pressure is removed. However, the prior art closure assemblies of this general type for the most part are bulky and cumbersome, and they do not adequately function as a complete and sanitary seal to prevent further discharge of the substance, and to provide an air-tight seal for the substance in the tube, when the squeezing pressure is removed.
The closure apparatus of the present invention, on the other hand, in its various embodiments serves as a complete closure for the substance in the collapsible tube until a squeezing pressure is applied to the tube, and then the closure acts to dispense a desired amount of the substance from the tube so long as the squeezing pressure is maintained. The closure assembly of the invention is strong, durable, and efficient in operation. Moreover, the closure assembly of the invention is sanitary, and it is capable of forming an air-tight seal to prevent further discharge of the substance in the tube, and to serve as a protecting means for the substance, whenever the squeezing pressure is removed. Moreover, the closure assembly of the invention, as will be described, is simple and inexpensive in its construction, and it is easy to use.